A broad photoluminescence (PL) band peaking at 1.70 eV in Li-doped GaP is investigated by optical spectroscopy. No electronic lines are observed for this PL spectrum, indicating a strong phonon coupling with a no-phonon energy of 1.80 eV. Optically detected magnetic resonance (ODMR) data reveal a triplet configuration for the lowest excited electronic state of the corresponding defect, which proves that it is a neutral complex defect, binding an exciton in a predominantly hole-attractive local potential with a compressive local strain field at the defect. The ODMR data can be fitted to a triplet spin Hamiltonian H=1/4BB g S+D[Sz2-(1/3)S (S+1)]+E(Sx2-Sy2) with evaluated parameters gx=2.0, gy=1.9, gz=2.05, D=1.2×10-5 eV, and E=8×10-7 eV x, y[11»0], z. The defect, therefore, has a bent symmetry, and the identity is suggested to involve LiGa together with two interstitials in a (110) plane, probably both Li atoms.